by Adam Johnston
When I hear “sustainability” and its root, I think of the sustain pedal on my piano; I think of sustenance; and, especially lately, I think about and worry about the sustaining of programs and people. I consider what I can sustain on a few hours of sleep. But it’s not really about me, or even a program, no matter how big and important. I know this is really about a bigger sustainability, sustaining, sustenance.
Lately I’ve been wrecking our sustainability by driving an extra car instead of riding the bus or my bike. I’ve wondered if I could, maybe just to alleviate my guilt, save the world by driving my girls to dance lessons. If I drive them to dance or violin, will they learn something that will make up for the refined fossil that I’ve just exhausted into the air they’re breathing. It’s a good question. I justify it. If they learn dance they’ll learn spatial skills and have a better understanding of calculus later. Maybe. If they learn violin they’ll learn patience and have a better sense of perseverance in graduate school. Perhaps. Or maybe they’ll just learn movement and music. Those are the hard questions, the ones that don’t have the coveted analytic solution.
There are easier problems. Call it the first law of thermodynamics or conservation of energy, but either way it’s the rule I think that determines our existence, actions, and limits more than any other natural law. With this, you can figure out exactly how fast you could possibly go when skiing down a mountain, and exactly how much gasoline I’ll use to pick up a daughter from any given class or lesson. In some ways, it reduces physics to accounting, but that’s not the image I like to portray too much. It’s accounting with sex appeal, because it’s more than just numbers on a page. It’s actions and potentials for action, and even if they’re hiding in a gallon of gasoline or in the nucleus of an atom, nature is keeping track, effortlessly and elegantly.
This first law of thermodynamics gives me hope. It is, in its very essence, sustainability writ large. It is the big constant of the universe, and with it a certain consciousness in an unconscious system. You know that if your planet starts orbiting faster or your star starts burning brighter that something else is making up for it. Everything is paid in full, and all the exchanges are equal and fair. Best of all, you can exchange energy back and forth without penalty. There’s no stockbroker fee or shipping charges.
But there is a catch. I’ll come back to that in a second. Let me interject one other point first. While I liken nature to this meta-accountant of energy, it’s easy to get caught up in the notion that it’s all just a giant ledger or some kind. Galileo’s notion that “mathematics is the language of nature” is nowhere more true, and best of all it’s mostly just simple addition and subtraction. In fact, the concept of energy and energy conservation was first thought up in order to better keep track of natural systems — an invention to help us predict what might happen next. Energy wasn’t an empirical thing, but a construction of quantities that just happened to be conserved in all exchanges. It made the physics easier. Ask any physics student about how much easier the problems get once they’re in chapter 5, where conservation of energy is introduced, and they’ll suddenly have a look of relief. Using this made up system is a great gimmick that gives them a tool to solve problems. It was all invented purely for this purpose.
So, imagine our surprise when it turned out to be a real thing. This struck me particularly hard somewhere around the third year of teaching College Physics. It’s subtle. Somehow I had found myself going full circle, from thinking that energy was real “stuff,” like the caloric of old, to thinking it was just accounting, and back again to thinking it was not “real” stuff but some other something. It was the mathematics that swayed and seduced me, showing me that energy exists in these “fields”. And, too, it’s in mass. Still, everywhere accounted for and, yes, sustained.
Right, but there was that one caveat, the “catch” I was suggesting earlier. That’s the second law of thermodynamics.
If I were to step outside and not be a fully objective scientist (and let’s not kid ourselves — I’ve yet to meet someone who really is all the time) I would be upset, angry, and simply pissed at the second law. Why? Because, first of all, it doesn’t give me, nor even allow for me, everything I want. And second, it’s inelegant. It’s a pain-in-the-ass piece of physics that simply derives from stupid statistics. In class, I try to derive and explain and animate the second law in a variety of ways, but it boils down to the idea that there are far more ways for systems, including the universe in its entirety, to be disorderly than orderly. That is, energy is much more likely to get spread out than it is to get hoarded into useful corners, shelves, or even habitable planets. And that means that, while energy is conserved, we can’t keep it. Your ice cream sundae will still have all its molecules in place, but it’s going to melt. Mountains erode. Gasoline becomes exhaust. The energy is still there, but it mostly, eventually, just contributes to a slightly higher temperature of deep space.
So my driving to dance and violin lessons had better be worth it.
It would be nice to end here with some rebounding lesson, some metaphor from nature that I can apply to life. It’s not there, though. Yes, everything is sustained, and at the same time everything erodes. We could, and should, slow this down. I’ll appreciate this, as my daughters, I hope, will dance and play in a world that might still be livable.